JP2017105172A - Liquid discharge head and method for manufacturing flow passage member of liquid discharge head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid discharge head that does not expose filler at a surface of a flow passage member in a liquid discharge head.SOLUTION: The liquid discharge head for discharging liquid includes the flow passage member provided with a flow passage coming into contact with the liquid, formed of a resin (3100) and filled with the filler (3210) coated with the resin (3200).SELECTED DRAWING: Figure 4

Description

  The present invention relates to a liquid discharge head and a method for manufacturing a flow path member of the liquid discharge head, and more particularly to a technique for forming a flow path member by filling a molding material such as resin with a filler.

  As an example of a liquid discharge head, an ink jet recording head (hereinafter also simply referred to as “recording head”) is formed by, for example, filling a resin with a support member that supports a substrate provided with an energy generating element. It has been known. Patent Document 1 describes that a support member for supporting a substrate in a recording head is formed by filling a resin with a filler. When forming the support member, the linear expansion coefficient can be reduced by using a filler, thereby reducing the stress that may occur between the substrates to be joined.

  The support member described in Patent Document 1 is provided with a flow path for ink communication between the ink supply chamber and the substrate, and is generally compared with alumina used as a material of the support member. It can be manufactured at low cost.

JP 2010-247508 A

  However, in the case where the flow path member formed with a flow path in contact with a liquid such as ink, such as the above-described support member, is formed by filling a molding material such as a resin with a filler, the filler on the surface of the molded product May be exposed and dissolved in a liquid such as ink. In particular, when a relatively large amount of filler is added to achieve a small linear expansion coefficient, the filler is exposed on the surface of the molded product, and is easily dissolved in the solution in the liquid. In this way, the filler dissolved in the solution may cause adverse effects such as clogging the nozzles of the recording head.

  In order to solve the above-described problems, the present invention provides a liquid discharge head for discharging a liquid, which is a flow path member formed of resin and provided with a flow path in contact with the liquid, and is covered with the resin. And a flow path member filled with a filler.

(A) And (b) is the side view and top view of the inkjet recording head which concern on one Embodiment of the liquid discharge head of this invention. FIG. 2 is an exploded perspective view of the recording head illustrated in FIG. 1. It is a flowchart which shows the process which forms a baseplate based on one Embodiment of this invention. (A) And (b) is a figure which shows the surface and cross section of the molded object which concerns on one Embodiment of this invention. (A) And (b) is a figure which shows the surface and cross section of the molding which concerns on a comparative example. 1 is an external perspective view of an ink jet recording apparatus including a recording head according to an embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  1A and 1B are a side view and a plan view of an ink jet recording head according to an embodiment of the liquid discharge head of the present invention. FIG. 2 is an exploded perspective view of the recording head shown in FIG.

  As shown in FIGS. 1A and 1B, a recording head 1000 according to this embodiment includes a plurality of recording element substrates 1100 arranged in a staggered manner, and constitutes the recording elements provided on the respective recording element substrates. Ink is ejected from the nozzle. In the recording head 1000, an electric wiring board 1300 is provided around each recording element substrate 1100, whereby an electrical signal is transmitted between the recording element substrate 1100 and the recording apparatus main body on which the recording head 1000 is mounted. It is possible to exchange such as. The recording head 1000 of the present embodiment is a full line type recording head. That is, the entire nozzles of the plurality of recording element substrates 1100 are arranged in a range corresponding to the width of the recording medium to be conveyed.

  As shown in FIG. 2, the recording head 1000 of this embodiment includes a recording element substrate 1100 formed of silicon (Si), a base plate 1200 for supporting the recording element substrate, a recording element substrate, and a recording apparatus. The electric wiring board 1300 for performing the electrical connection and the ink supply member 1500 bonded to the base plate 1200 are configured. The plurality of recording element substrates 1100 are arranged in a staggered manner on the main surface 1200a of the base plate 1200 in a direction intersecting the conveyance direction of the recording medium, and an ink supply member 1500 is bonded to a surface 1200b opposite to the main surface 1200a. The In this configuration, the ink stored in the ink storage unit 1510 provided in the ink supply member 1500 passes through the ink supply slit 1210 provided in the base plate 1200 corresponding to each recording element, and the recording element substrate 1100. In each of the nozzles is supplied to a pressure chamber provided with a heating heater.

  In this way, the ink flow path (slit 1210) is formed in the base plate 1200. As will be described in detail later, the base plate 1200 is formed by filling a resin with a filler.

  Below, the material and formation method which form the baseplate 1200 as a flow-path member are demonstrated. Here, the base plate according to the embodiment of the present invention is such that the filler mixed in the forming resin is coated with a resin different from the forming resin, as will be described later with reference to FIG. This prevents the filler itself from being exposed on the surface of the base plate.

  First, the filler mixed in the forming resin will be described as a material to be formed. Examples of the filler used in the present embodiment include silica, fused silica, calcium carbonate, hydrated alumina, zircon cordierite, mica, talc, magnesium hydroxide, and glass floss. The shape of the filler in the present invention is not particularly limited, but a spherical shape is preferable for increasing the filling rate, and it is desirable to mix particles having different particle diameters in order to achieve close packing. The ratio of those having different particle diameters is preferably about large: small = 9: 1 to 6: 4.

  In particular, fused silica has a low coefficient of linear expansion and is inexpensive. In addition, since it has a spherical shape, it is possible to mix various particle sizes for close packing. Since the glass fiber is fibrous, before the cut fiber process in the pulverizer, it is possible to prevent the fibers from aggregating by providing a coating film by a method such as immersing in a coating liquid described later and then pulling it up. In addition, the coating film thickness can be easily controlled.

  Moreover, you may use a filler in mixture of multiple types according to a required characteristic. For example, when used in a container of a strong alkaline solution, good resistance can be obtained by using alumina with high chemical resistance.

  Next, the resin for coating the filler is not particularly limited. When the resin is a thermoplastic material, it preferably has a melting point sufficiently higher than the kneading temperature with the filler described later and the resin temperature at the time of molding. At least the melting point of the resin covering the filler is preferably higher than the melting point of the resin for molding the flow path member. Thereby, since the melting of the coating resin member of the filler can be suppressed even in the heating state when the base plate is molded, the exposure of the filler due to the melting of the coating resin member can be suppressed. An example thereof is Hitachi Chemical's HIMAL, which is a polyether amide resin. HIMAL has a high glass transition temperature and good chemical resistance. On the other hand, when the resin is a thermosetting resin, examples thereof include a phenol resin, a urea resin, a melamine resin, and an unsaturated polyester resin. Among these, an epoxy resin can be preferably used from the viewpoint of adhesion to a filler, resistance to ink, and the like. Here, the epoxy resin refers to an epoxy resin composition composed of an epoxy resin, a curing agent, a curing accelerator, a silane agent, and the like. Since the solution is used when the filler is coated, it may be either solid or liquid.

  Among the epoxy resin compositions, epoxy resins include bisphenol A type epoxy, bisphenol F, bisphenol AD, and glycidyl ether, epoxy novolac resin, bisphenol A novolac diglycidyl ether, and bisphenol F. Examples thereof include glycidyl ether type such as novolak diglycidyl ether, glycidyl amine type epoxy, and alicyclic epoxy. Further, not only a liquid resin but also a solid resin may be used because it only needs to be liquid as a resin composition. Examples of the solid material include an epoxy having a biphenyl skeleton, a naphthalene skeleton, a cresol novolak skeleton, a trisphenolmethane skeleton, a dicyclopentadiene skeleton, a phenol biphenylene skeleton, and the like.

  There is no restriction | limiting in particular as a hardening | curing agent among an epoxy resin composition. For example, amine, tertiary amine, polyamide, acid anhydride, imidazole, phenol and the like can be used. Furthermore, the thing which added the epoxy resin to these and improved pot life and reactivity can also be used. For acid anhydrides as curing agents, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic acid anhydride, hydrogenated methylnadic acid anhydride, trialkyltetrahydrophthalic anhydride An acid etc. are mentioned. Examples of imidazole include 2-ethyl-4-methylimidazole and 1- (2-cyanoethyl) -2-ethyl-4-methylimidazole. Examples of solid curing agents include phenol curing agents, but xylylene novolak, biphenyl novolak, dicyclopentadiene phenol novolak, and the like.

  In addition, you may add a flexibility imparting agent and another additive to the above resin composition by the method used normally. Examples of the flexibility imparting agent include alcohol-modified epoxies such as general 1,6-hexanediol diglycidyl ether and glycerin triglycidyl ether, urethane-modified epoxies, and silicone-modified epoxies. Moreover, for example, 1,1,3,3-tetramethyl-1,3-diglycidyl ether disiloxane having a siloxane bond in the main chain may be mentioned.

  Of the epoxy resin composition, a silane coupling agent can also be added. Examples of the silane coupling agent include γ-glycidoxypropyltrimethoxysilane, β- (3,4 epoxycyclohexyl) -ethyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, and the like. It is done. Further, titanate or aluminate may be used.

  The coating thickness when the filler is coated with the resin composition is not particularly limited, but if it is too thick, the effect of adding the filler is reduced in terms of reducing the linear expansion coefficient, and the filling amount into the molding resin In addition, the fillers are likely to aggregate due to the coating and individual fillers may not be coated. From the above points, the coating thickness is 0.1 μm or less, preferably 0.05 μm or less, although it depends on the size of the filler.

  Next, examples of the forming resin for kneading the filler include PPS, modified PPE, and LCP. You may mix and use these. For example, a relatively inexpensive PPS or modified PPE can be mixed. In that case, PPS is a material having high heat resistance and high fluidity, while modified PPE is characterized by excellent adhesion, film property, and mechanical properties. For this reason, when a relatively large amount of filler is added as in this embodiment, the fluidity of the molding material itself is greatly reduced. Therefore, the proportion of PPS is increased to ensure fluidity, and the adhesiveness with the filler is increased. In order to maintain the property, it is preferable to use a modified PPE in combination.

  The amount of coated filler added varies depending on the type and shape, and the melt viscosity of the molding resin. However, if the mass content is added to the molding resin at 60% or more, the filler appears on the molding surface. This increases the ratio, and the effects of the present invention can be exhibited effectively. For example, when fused silica is used as the filler, the effects of the present invention are suitably exhibited when 75 wt% or more is added.

  Next, a method for forming the base plate 1200 will be described.

  FIG. 3 is a flowchart showing a process for forming a base plate made of the material described above.

  First, in step S31, a coating resin is prepared. Table 1 shows two epoxy resin compositions as coating resins. In Table 1, the composition indicated by “1” is liquid, and the composition indicated by “2” is solid. In the following description, examples (hereinafter referred to as Example 1 and Example 2) in which a filler coating is prepared using each of these epoxy resin compositions 1 and 2 will be described. Since they are the same, the first and second embodiments will be described without distinction. The compositions 1 and 2 contain a silane coupling agent, but the silane coupling agent is not essential if the filler itself is subjected to silane treatment. However, the inclusion in the composition is more effective in improving the adhesion with the filler.

  Next, a coating resin solution is prepared (prepared) in step S32. Specifically, the above-described epoxy resin composition is mixed at a weight ratio of 1: 1 using MEK to prepare a solution. The type of the melting material and the ratio of the solvent are not limited to this example. However, when kneaded with a filler, it needs to be in a solution state. This is because if the solution is not in a solution state, the entire filler cannot be surely covered with the resin solution, so that defects such as pinholes may occur on the filler surface.

  Next, in step S33, the solution prepared in step S32 and the filler are mixed. Here, the filler used was HS-304 manufactured by Micron Corporation, which is a spherical fused silica, and has an average particle size of 25 μm and a low particle size cut product. The particle diameter is not limited to this, and several kinds of particles having different particle diameters can be combined for the closest packing. The reason why low particle size cut products are used is that when the ratio of low particle size products is high, the low particle size products aggregate through the coating resin, and the coated resin does not spread over the entire filler.

  In this step, first, the silane treatment of the filler is performed. That is, 10 kg of filler is put into a Henschel mixer. Then, while stirring at 700 rpm, a solution consisting of 7 g of A-187 and 500 g of ethanol is added and stirred for 5 minutes. After confirming that the whole is a uniform viscous solution, add steam. When the solvent evaporates due to the steam, the rotation speed of stirring is set to 1400 rpm, the temperature is kept at 100 ° C. for 5 minutes, and then cooling is performed.

  Next, the filler is coated with a coating resin. That is, 800 g of each of the solutions of the epoxy resin compositions 1 and 2 is an amount of a solution having a coating thickness of 0.05 μm calculated from the specific surface area of the filler while stirring at a low speed of about 50 rpm with a Henschel mixer after cooling. throw into. Thereafter, stirring is performed for 5 minutes.

  In step S34, it is confirmed that the whole is a uniform viscous solution. And it stirs at 1000 rpm for 10 minutes so that the solution of the epoxy resin composition 1 and 2 may spread over each of each filler. Thus, by using the solution of a thermosetting resin, the resin composition can be spread over the entire filler regardless of whether the resin composition is viscous liquid or solid.

  Next, in step S35, the rotational speed is lowered to 700 rpm, steam is added (heated), and the solvent is evaporated. Thus, the resin can be uniformly coated on each filler by heating and removing the solvent while stirring.

  Further, in step S36, heating and stirring are continued and stirring is performed at 150 ° C. for 60 minutes to cool the coated resin member after curing. By heating with stirring, the coated resin member can be cured without the fillers being bonded to each other. For the filler coated with the resin composition 2, additional heating at 200 ° C. for 1 hour is performed in an oven in order to increase the degree of crosslinking. Since the resin composition 2 is cured by heating in a Henschel mixer, the fillers do not adhere to each other even if additional heating is performed. Through the above steps, a filler coating is produced in which each spherical filler is covered with a coating resin member. Each filler coating has a core-sheath structure in which the outer core is a coated resin member and the inner core is a filler, and the outer shape of the filler coating is substantially spherical.

  Next, the process of mixing the filler coating obtained by coating the filler with the resin described above with reference to FIG. 3 with the resin for forming the base plate will be described below.

  First, as the molding resin for molding the base plate, a resin different from the above-described filler-coated resin member is used. Specifically, B-060P (manufactured by Tosoh Steel Corporation) is used as PPS, and Zylon SX101 (Asahi Kasei Chemicals) is used as the modified PPE. Then, the PPS and the modified PPE are pulverized and mixed at a ratio of 4: 1.

  Next, as described above, the coated filler is HS-304 coated with the resin composition 1 in Example 1, and HS-304 coated with the resin composition 2 in Example 2. Moreover, HS-304 which is a filler itself which is not coated as Comparative Example 1 and HS-304 which is a filler itself which is not similarly coated are used as Comparative Example 2.

  For each of these fillers, the ratio of the molding resin to the filler described above was kneaded with a uniaxial extruder at a weight ratio of molding resin: filler = 20: 80 and pelletized. Obtained.

  The evaluation results for the four molded articles of Examples 1 and 2 and Comparative Examples 1 and 2 prepared as described above are as follows.

  FIGS. 4A and 4B are views showing the surface and the cross section of the molded product according to Examples 1 and 2. FIG. 5A and 5B are views showing the surface and cross section of the molded products according to Comparative Examples 1 and 2. FIG.

  Since all of the four molded products have a relatively high filler content, the filler may be exposed on the surface of the molded product. On the other hand, the molded products of Examples 1 and 2 are exposed as a resin-coated filler 3200 in which the filler is covered with a coating resin, as shown in FIG. Specifically, in a state where the resin-coated filler 3200 is mixed in the molding resin 3100, a part thereof is exposed on the surface of the molded product, but the filler is in a state where the whole is coated with the resin. That is, in the molded products of Examples 1 and 2, when the resin-coated filler 3200 is cut as shown in FIG. 4B, the filler 3210 shown in white is the resin shown in black. It is in a covered state.

  On the other hand, in the molded products according to Comparative Examples 1 and 2, as shown in FIG. 5A, when the filler is exposed on the surface of the molded product, the filler 4200 itself that is not covered with the resin appears. As can be seen from the cross-sectional view of FIG. 5B, in the same figure, the filler 4200 shown in white is mixed in the molded product without any covering.

  As described above, in each of Examples 1 and 2 according to the embodiment of the present invention, even when the filler is exposed on the surface of the molded product, the filler is covered with the resin. Thereby, when a molded object is a base plate (flow path member) like this embodiment, it can prevent that a filler melt | dissolves in liquids, such as an ink.

  In a specific evaluation experiment, 10 g of a molded product produced by the above production method was immersed in 200 g of black ink at a temperature of 60 ° C. for one month, and then the elution amount of the filler in the ink was measured. In 1 and 2, almost no elution could be confirmed at 1 ppm or less. On the other hand, in Comparative Examples 1 and 2, about 10 ppm of filler elution was observed.

<Device configuration>
FIG. 6 is an external perspective view of an ink jet recording apparatus according to an embodiment of the liquid ejection apparatus of the present invention. The ink jet recording apparatus 1 includes long recording heads 2Y, 2M, 2C, and 2Bk that extend in a direction (Y direction: first direction) that intersects the conveyance direction (X direction: second direction) of the recording medium P. Is a full line type printer which is arranged side by side as shown in the figure. Here, 2Y is a recording head for ejecting yellow ink, 2M is a recording head for ejecting magenta ink, 2C is a recording head for ejecting cyan ink, and 2Bk is a recording head for ejecting black ink. These recording heads are provided with the base plate manufactured in the manufacturing process described in the above-described embodiment. The recording head 2 is connected to four ink tanks 3Y, 3M, 3C, and 3Bk (hereinafter collectively referred to as ink tanks 3) that store yellow ink, magenta ink, cyan ink, and black ink, respectively. Connected through. Further, each of the ink tanks 3 can be replaced with respect to the connection pipe 4.

  The control device 9 controls each mechanism shown in the drawing in order to control the entire operation of the ink jet recording apparatus 1. When performing the recording operation, the control device 9 first drives the feeding motor 15 by the motor driver 16 to rotate the pair of feeding rollers 14. With this rotation, the recording medium P is fed in the X direction in the figure. Next, the control device 9 drives the motor driver 12 to rotate the belt drive motor 11. By this rotation, the driving roller 17 connected to the belt driving motor 11 rotates, and the conveying belt 5 stretched around this moves. Further, the controller 9 operates the charger 13 provided upstream of the conveying belt 5 by driving the charger driver 13a, and charges the recording medium P fed thereto. The charged recording medium P is attracted to the transport belt 5 and transported at a predetermined speed in the X direction as the transport belt 5 moves.

  A platen 6 that supports the recording medium P from below and a recording head 2 for recording on the recording medium P at this position are arranged at a recording position in the conveyance path. Each nozzle of the recording head 2 is electrically connected to the control device 9 via the head driver 2a, and ejects ink in accordance with a drive signal transmitted from the control device 9. Thereby, dots are recorded on the recording medium P that moves relative to the recording head. The control device 9 controls the speed at which the recording medium P is conveyed and the frequency at which ink is ejected from each recording head 2 in an appropriate relationship, whereby an image is recorded on the recording medium P with a predetermined resolution.

  When executing the recovery process for the recording head 2, the control device 9 drives the head moving means 10 to raise the recording head 2 once in a direction away from the platen 6. Thereafter, the cap moving unit 8 is driven to move the cap 7 directly below the recording head 2, and the head moving unit 10 is further driven to lower the recording head 2 toward the cap 7. The cap 7 receives waste ink discharged from the discharge port while covering the discharge port surface of the recording head 2 or forcibly sucks ink from the discharge port.

(Other embodiments)
The recording head of the above-described embodiment is of a full line type, but is not limited to this form. For example, the present invention may be applied to a support member for a so-called serial type recording head.

Of course, the member to which the present invention is applied is not limited to the support member described above. Any member may be used as long as the member is in contact with a liquid such as ink (referred to as a “flow channel member” in this specification). For example, it may be provided in a liquid storage section that stores liquid, or may be provided in at least a part of a liquid communication path that connects the liquid storage section and the liquid ejection head.
According to the above configuration, it is possible to provide a liquid discharge head in which the filler is not exposed on the surface of the flow path member in the liquid discharge head.

1000 Recording Head 1100 Recording Element Substrate 1200 Base Plate 1210 Ink Supply Slit 1300 Electric Wiring Board 1500 Ink Supply Member 1510 Ink Storage Unit 3100 Molding Resin 3200 Resin Covered Filler 3210 Filler

Claims (11)

A liquid discharge head for discharging liquid,
A flow path member formed of a first resin provided with a flow path in contact with the liquid;
A core-sheath coated resin member comprising a filler constituting the inner core and a second resin constituting the outer core;
And the flow path member includes a plurality of the coating resins.   The liquid discharge head according to claim 1, wherein a melting point of the second resin covering the filler is higher than a melting point of the first resin forming the flow path member.   The liquid discharge head according to claim 1, wherein the second resin covering the filler is thermosetting.   4. The liquid discharge head according to claim 1, wherein the second resin that covers the filler is an epoxy resin composition. 5.   The liquid discharge head according to claim 1, wherein a mass content of the filler in the flow path member is 60% or more.   The liquid discharge head according to claim 1, wherein the filler is fused silica.   The liquid discharge head according to claim 1, wherein the coating resin member has a spherical shape. A method of manufacturing a flow path member of a liquid discharge head,
A step of mixing a resin solution and a filler to form a solution;
Heating to remove the solvent while mixing in the solution state;
Heating while performing the mixing, curing the resin, creating a core-sheath coated resin member composed of a filler constituting the inner core and a resin constituting the outer core;
A kneading step of kneading a plurality of the covering resin members and a molding resin for molding the flow path member;
A method of manufacturing a flow path member of a liquid discharge head, comprising:   9. The method of manufacturing a flow path member for a liquid discharge head according to claim 8, wherein the melting point of the resin contained in the coating resin member is higher than the melting point of the molding resin. A liquid discharge apparatus including a liquid discharge head for discharging liquid,
A flow path member formed of a first resin provided with a flow path for supplying a liquid;
A core-sheath coated resin member comprising a filler constituting the inner core and a second resin constituting the outer core;
And the flow path member includes a plurality of the coating resins.   11. The liquid ejection apparatus according to claim 10, wherein the flow path member is provided in a path that communicates a liquid storage section that stores a liquid and the liquid ejection head.